Method and apparatus for applying fluid materials to moving surfaces



Oct. 10, 1933.

E. H. MERRITT ET AL METHOD AND APPARATUS FOR APPLYING FLUID MATERIALS TOMOVING SURFACES Filed May 8, 1931 4 Sheets-Sheet 1 IN VEN T0 BY W IkaJ-WY" Mum} ATTORNEYS.

Oct. 10, 1933. E. H. MERRITT ET AL METHOD AND APPARATUS FOR APPLYINGFLUID MATERIALS TO MOVING SURFACES Filed May 8, 1931 4 Sheets-Sheet 2INVENTORS.

ATTORNEYS.

Oct. 10, 1933. E. H. MERRITT ET AL METHOD AND APPARATUS FOR APPLYINGFLUID MATERIALS T0 MOVING SURFACES 4 Sheets-Shet 5 Filed lay 8, 1951 & mMm T m m. +R V m w. W fi W w Oct. 10, 1933. E. H. MERRITT El AL v1,929,896

METHOD AND APPARATUS FOR APPLYING FLUID MATERIALS TO MOVING SURFACESFiled May 8, 1951 4 Sheets-Sheet 4 7 INVTENTgffZ 4- MW ATTORNEYS.

Patented Oct. 10, 1933 UNITED STATES PATENT OFFICE METHOD AND APPARATUSFOR APPLYING FLUI]; MATERIALS TO MOVING SUR- FACE Seattle, Wash, acorporation of Delaware Application May 8, 1931.

18 Claims.

This invention relates to methods and apparatus for applying fluidmaterials to surfaces, and in its more particular aspects to theapplication of fluid materials to moving surfaces.

An object of the invention is to provide an im proved method forapplying fluid materials to surfaces.

A further object is to provide an improved method for spraying movingsurfaces of relatively large area.

Another object is to provide improved means .for applying fluidmaterials to surfaces.

A further object is to provide means for progressively spraying asurface in a particularly uniform manner.

A still further object' is to provide improved means for applying afluid to surfaces of relatively large area.

Another object is to provide means adapted to spray moving articles in aparticularly effective manner.

An additional object is to provide apparatus of the character underconsideration which is simple in construction and economical tomanufacture, which may be readily assembled and operated, and which willeffectively perform the functions for which it is intended.

Other objects of the invention will in part be obvious and.will in partappear hereinafter.

The invention accordingly comprises the several steps and the relationand order of one or more of such steps with respect to each of theothers, and the apparatus embodying features of construction,combinations of elements and arrangement of parts, all as exemplified inthe following detailed disclosure, and the scope of the application ofwhich will be indicated in the claims.

For a fuller understanding of the nature and objects of the inventionreference should be had to the following detailed description taken inconnection with the accompanying drawings, in

' which:

Serial No. 535,822

Fig. 6 is a diagrammatic showing of the course followed by the sprayingmeans;

Figs. 7a, 7b, 7c and 7d illustrate the progressive coating of a surfaceby means of apparatus such as shown;

Fig. 8 is an enlarged view of the exemplified spraying gun; and

Fig. 9 is a plan view of the cam, showing the manner of plotting thecurves for its periphery.

The invention contemplates the provision of means for applying any of alarge number of fluid substances, including gases, liquids, andcomminuted solids, to articles of a wide variety of different naturesfor any of a number of purposes. It is especially intended, however, foruse in the solution of numerous problems which present themselves incases where it is desired to apply a uniform and even spread of fluidmaterial to a surface. One such case is found in the adhesive art wherea plasticizing agent for an adhesive material should be applied to asurface, such, for example, as the surface of a veneer sheet, in anespecially uniform and even manner in order that the plasticizing effectwill not be exerted so irregularly as to cause such irregulari- 30 tiesin adhesion as will militate against the production of glued structures,such, for example, as plywood, of particularly high quality. Again, inthe application of liquid adhesive materials there are similardesiderata, and it is of particular im- 35 portance that, while asuificient quantity of glue should be supplied at all points, an excessof glue at any point should be avoided so far as possible in order notonly to prevent gluing troubles but also to prevent a wastage of glue.The prevention of such wastage is of special importance in the use ofrelatively expensive glues certain of which have been utilized to arelatively small extent in spite of their desirable qualities because ofthe difficulties involved in applying them without waste.

The invention also has many applications inthe coating art wherein inmany cases the desirability for a uniform and even spread is alsopresent.

The invention is designed for the application of powdered materials aswell as liquid materials, and also for the application of gaseousmaterials, such as may have a desirable effect in the treatment of wood,for example. Such application may be accomplished by spraying thematerial against the surface. In this connection, it is to be noted thatthe word spraying as used,herein is intended to include all modes ofprojection of Y1110 a substance and that all expressions including theterm spray are to be similarly understood.

In many cases, and particularly where a fluid material is to be appliedto relatively large surfaces, there are many difficulties in the utilization of a spray whichis sufiiciently wide so that the entire surface maybe sprayed at a single simple movement, either of the spray or of thearticle to be sprayed, and the invention contemplates the provision ofmeans for satisfactorily coating articles in a progressive mannerinvolving the movement of a spray of relatively small area with respecteither to the direction of movement of a moving surface, or with respectto the direction of movement of a spray carriage. Ordinarily the simplerprocedure is to move an article to be sprayed, and preferably a seriesof such articles, along a path beneath a spraying means, and theinvention is particularly exemplified as embodied in a spraying meansadapted to move back and forth above the path of movement of articlescarried on a conveyor.

The form of apparatus particularly exemplified comprises a conveyor 10above which spraying mechanism is mounted on a suitable frame-work 11.The spraying mechanism comprises a gun 12 provided with a nozzle portion13 from which a liquid or other material of a sufficiently fluid natureto be sprayed is directed downwardly. By

means of flexible conduits 14, in the present instance, the liquid to besprayed and suitable fluid pressure means are conducted to the gun. Thegun is carried on a carriage 15 riding on a .pair of track members 16 bymeans of rollers 17.

In order to cause a timed reciprocation of the carriage and to controlthe acceleration and deceleration thereof to avoid jerkiness of themovement, the exemplified apparatus comprises a chain extending aboutsprockets 18 and 19 and carrying a roller 20. This roller is heldbetween bars 21 and 21a extending transversely of the chain and forminga part of the gun carriage 15, so

.that, as the roller moves with the chain, the carriage will be movedfirst in one direction and then in the other, with gradual decelerationand acceleration movements as the roller is carried through asemi-circular course about each sprocket wheel. With each change ofmovement the gun will move first in one direction and then in the otheracross the conveyor.

In order to avoid undesirable irregularities in the application of thematerial sprayed on a surface moving on the conveyor, there are providedmeans to cause the gun to follow, during each of its movementstransverse to the conveyor, a diagonal course which carries it .towardthe output end of the conveyor. To this end the track members 16, in thepresent instance, are adjustably mounted and means are provided forcausing them to swing upon a vertical axis in synchronism with portionsof the carriage movement. In the exemplified form of apparatus thetracks are supported on course members 22 by means of rollers 22acarried on braces 23 extending between the tracks, and there is providedat either side of the center of the tracks holding members 24 eachcomprising an annulus 25 against which the outside of a track memberrests. These supporting members are preferably arranged so as to permita slight change in the distance between them due to oscillatingmovements of the tracks. In order to oscillate the tracks there areprovided a pair of spaced rollers 26 mounted, in the present instance,on a slide member 28 which is in turn disposed to ride between guidestrips 280 which 'part of the general frame structure 11.

are suitably fastened to plate 28b which forms a Connected to andextending downward from both ends of slide member 28, arms 29 areadapted totransfer the motion of slide member 28 to tracks 16 throughthe additional agency of spring plungers 29a which are fitted intosuitable bosses in the lower ends of arms 29 and which bear against thesides of rails 16. Between rollers 26 there is provided a cam member 30mounted on a shaft 31 extending through a slot 31a in the slide member28.

Suitable driving means for the chain 1'7 and the cam 30 are provided. Inthe present instance, such means include a shaft 32 upon which thesprocket wheel 18 is carried, and a gear 33 on the shaft 32 and meshingwith a gear 34 on the shaft 31. The shaft 32 also carries a beveled gear35 meshing with a bevel gear 36 within a gear case 36a and connectedwith a sprocket 37 by a shaft 37111 A drive-chain 38 extending over thesprocket 3'7 connects the latter with a source of power such as theelectric motor 39, in the present instance. In the exemplifiedapparatus, this connection is through the medium of variable speedmechanism, as indicated at V, whereby the speed of movement of thesprocket 3'7 and the conse quent speed of movement of the gun and thespeed of oscillation of the track may be conveniently regulated withrespect-to the speed of the conveyor in the particular case.

Any suitable means, including, for example, sprockets 40 and 41 and achain 42, may likewise be provided for driving the conveyor, andvariable speed mechanism as indicated at W and operated from,a suitablesource of power, such as a motor 43, may likewise be inserted in theconveyor drive, if desired.

The exemplified cam 30 is so constructed, as indicated in Fig. 9, thatits larger and smaller quadrants bisected by its axis of symmetry haveperipheries which are true arcs and its intermediate quadrants areformed with peripheries so arranged, in the present instance, that therolls travel thereover in a regular and even manner. As will be seen,the periphery of the small quadrant A is a true arc, the periphery ofthe large quadrant C is a true arc, and the quadrants B and D have aperiphery following a curve so plotted that the axis of a roller, suchas 26, will follow a curve plotted through a series of points ofintersection of equally spaced radial lines from the axis of the drivingshaft with circular lines having their center at the axis of the drivingshaft. These circular lines are drawn so as to intersect equally spacedpoints on a semi-circle Whose radius is equal to the diameter of theroll, which in turn is equal to half the difference between the radii ofthe smaller and larger arcuate peripheral portions of the cam, and theperipheral diameter of which is a radial line from the axis of theshaft.

It is to be noted in this connection that the course of the gun in itsreciprocation is such that it is beyond the conveyor at the outerportion of its course at each end thereof. Accordingly, with the cam 30formed in the manner indicated and the cam disposed so that the rollswill traverse the peripheries of the quadrants A and C at the centralportions of the course of the gun in each direction, the course of thegun during each period when it is over the conveyor will be a straightline, since there is no change in the position of the rolls 26 withrespect to the axis of the cam during this period.

The direction of the movement of the gun carriage is illustrateddiagrammatically in Fig. 6. It will be observed that from the point E tothe point F the gun carriage moves along a straight line extendingdiagonally across the plane of the conveyor and inclined in thedirection of movement of the conveyor; that from the point F to thepoint G the gun carriage reverses its direction of movement and movesrearwardly with respect to the direction of movement of the conveyor;that from the point G to the point H the gun again moves in a straightline in a diagonal direction inclined toward the direction of movementof the conveyor; and that from the point H to the point E the .gun againreverses its direction and moves rearwardly with respect to thedirection of movement of the conveyor. Accordingly, if the spray gun isarranged to lay down a band the width of which is twice the distancefrom E to H or from G to F, the relative speeds of the conveyor and thesprocket 37 may be so arranged that the conveyor will move the surfaceof the member to be coated a distance equal to the distance between Eand H or G and F, at each quarter rotation of the cam.

For example, if the mechanism is timed so that the cam rotates once intwo seconds,-i. e., so that each of the four phases of the cycle isonehalf second in duration, and if the conveyor is arranged to move anarticle, such as a. veneer sheet, six inches a second, the veneer sheetwill move three inches as the gun travels above it at spaced intervals,and accordingly the travel of the gun with respect to the veneer sheetwill be in a line directly across the veneer sheet and perpendicular tothe direction of its movement. Consequently, the gun will traverse aseries of parallel paths each directly across the sheet and if the gunis arranged to deliver a spray of a given width, for example, 6" in theinstance taken, the sheet will receive a complete and substantiallyuniform coating of the material sprayed. This will be seen moreparticularly from Figs. 7a to 7d wherein Fig. 7a shows a veneer sheetafter the gun has travelled from E to F; Fig. 7b the same veneer sheetafter the gun has travelled from F to G; Fig. 7c the sheet after the gunhas travelled from G to H; and Fig. 7d the sheet after the gun hastravelled from H to E.

Thus, by causing the gun to reciprocate, and by causing a synchronizedintermittent oscillation of the tracks such that the tracks remainstationary in a diagonal position, when the gun moves above the conveyorsituated beneath the center of the tracks, there is obtained an evenback-and-forth movement of the gun whereby a very close approach touniformity in the coating of an article can be obtained.

It will be seen that by means of the mechanism exemplified the bandsprayed by a given movement of the spray means never crosses anotherband, nor is the space between the center of the bands any greaterdistance apart at one side of the surface than at the other.

It will be appreciated that the invention in its broaderaspects is notlimited to the use of spraying mechanism which is mounted on stationarysupports above a moving conveyor, and that, in certain instances, theentire spraying mechanism may be moved adjacent a stationary article tobe sprayed.

Any desired type of spraying means may be utilized to suit therequirements of a particular case, but in choosing such spraying meansit is desirable to select one which will give an even, regular spray inan effective manner. The particular spray means exemplified in Fig. 1 isshown in somewhat larger scale in Fig. 8. As will be seen the gun 12comprises a spray nozzle portion 13 and suitable inlet means 44, 45 and46 through which liquid and fluid under pressure may be introduced in adesirable manner.

Since certain changes in carrying out the above method and in theconstructions set forth, which embody the invention may be made withoutdeparting from its scope, it is intended that all matter contained inthe above description or shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific feaiures of the invention hereindescribed, and all statements of the scope of the invention which as amatter of language might be said to fall therebetween.

Having described our invention, what we claim as new and desire tosecure as Letters Patent is:

1. Apparatus for applying fluid materials to surfaces, comprisingspraying means, a track for said spraying means, means to cause saidspraying means to move back and forth along said track while ejectingliquid in a given direction, means to mount said track for oscillationon an axis intermediate its ends, and means to cause said track to movein one direction about said axis when the spraying means is adjacent oneend of its course and to move in the other direction about its axis whenthe spraying means is adjacent the other end of its course, and toremain stationary at intermediate periods.

2. Apparatus for applying fluid materials to surfaces, comprisingspraying means, a track for said spraying means, means to cause saidspraying means to move back and forth along said track, means to mountsaid track for oscillation on an axis intermediate its ends, and meansto cause said track to move in one direction about said axis when thespraying means is adjacent one end of its course and to move in theother direction about its axis when the spraying means is adjacent theother end of its course, and to remain stationary at intermediateperiods, the track-moving means comprising a cam member having aperiphery composed of oppositely-disposed arcuate portions of differentradii and intermediate portions joining said arcuate portions. 3.Apparatus for appying fluid ma'erials to surfaces, comprising sprayingmeans, a track for one end of its course and to move in the otherdirection about its axis when the spraying meansis adjacent the otherend of its course, and to remain stationary at intermediate periods, thetrack-moving means comprising a cam member having a periphery composedof oppositely-disposed arcuate portions of difierent radii andintermediate porlions joining said arcuate portions, each of saidarcuate portions defining substantially a quadrant of said cam.

4. Apparatus for applying fluid materials to surfaces, comprisingspraying means, a track for said spraying means, means to cause saidspraying means to move back and forth along said track, means to mountsaid track for oscillation on an axis intermediate its ends, and meansto cause said track to move in one direction about said axis when thespraying means is adjacent one end of its course and to move in theother direction about its axis when the spraying means is adjacent theother end of its course, and to remain stationary at intermediateperiods, the track-moving means comprising a cam member having aperiphery composed of oppositely-disposed arcuate portions of diiferentradii and intermediate portions joining said arcuate portions. saidintermediate portions being formed to provide even and regular curves.

5. Apparatus for applying fluid material to surfaces, comprisingspraying means, a track for said spraying means, means to cause saidspraying means to move back and forth along said track, means to mountsaid track for oscillation on an axis intermediate its ends, means tocause said track to move in one direction about said axis when thespraying means is adjacent one end of its course and to move in theother direction about its axis when the spraying means is adjacent theother end of its course and to remain stationary at intermediateperiods, the track-moving means comprising a cam member and a pair ofrollers embracing the same, and a rotatable shaft, said cam member andsaid pair of rollers being mounted one on said track and one on'saidshaft, and said cam member having a periphery composed ofoppositely-disposed arcuate portions of different radii and intermediateportions joining said arcuate portions.

6. Apparatus for applying fluid material to surfaces, comprisingspraying means, a track for said spraying means, means to cause saidspraying means to move back and forth along said track, means to mountsaid track for oscillation on an axis intermediate its ends, means tocause said track to move in one direction about said axis when thespraying means is adjacent one end of its course and to move in theother direction about its axis when the spraying means is adjacent theother end of its course and to remain stationary at intermediateperiods, the track-moving means comprising a cam member and a pair ofrollers embracing the same, and a rotatable shaft, said cam member andsaid pair of rollers being mounted one on said track and one on saidshaft, said cam member having a periphery composed ofoppositely-disposed arcuate portions of different radii and intermediateportions joining said arcuate portions, and said rollers having adiameter equal to one-half the difference between the radius of thearcuate portion of smaller radius and the radius of the arcuate portionof larger radius.

7. Apparatus for applying fluid materials to surfaces, comprisingconveyor means, track means above said conveyor means and extendingbeyond either side thereof, spraying means reciprocable on said trackmeans, means to oscillate said track means about a central axis in onedirection when the spraying means is. adjacent one end of said trackmeans and in the other direction when the spraying means is adjacent theother end of the track means, and means to drive said conveyor means andto impart reciprocation to said spraying means, said driving means beingarranged for adjusting the relative speeds of movement of said conveyormeans and said spraying means.

8. Apparatus for applying fluid materials to surfaces, comprisingspraying means, a carriage therefor, track means for said carriage,means for reciprocating said carriage on said track means withcontrolled accelerating and decelerating movements at the ends of thereciprocatory movements, and means including a cam member foroscillating the track means about a central axis inone direction wherethe spraying means is adjacent one end of said track means and in theother direction when the spraying means is adjacent the other end of thetrack means.

. 9. Apparatus for applying fluid materials to surfaces, comprisingspraying means, a carriage therefor, track means for said carriage,means for reciprocating said carriage on said track means, said meansincluding a pair of wheel members and an endless chain extending oversaid wheel members, and means for transmitting to said carriage theback-and-forth movement of a point on said chain in directions parallelto a line connecting the axes of said wheel members, means to mount saidtrack means to permit the same to be oscillated about a central axis, apair of control members carried by said track means at a point betweenthe pivotal point and one end thereof, a rotating cam member embraced bysaid control members, and means for driving said-chain and said cammember in synchronism.

10. Apparatus for applying fluid materials to surfaces, comprisingspraying means, a carriage therefor, track means for said carriage,means for reciprocating said carriage on said track means, said meansincluding a pair of wheel members and an endless chain extending oversaid wheel members, and means for transmitting to said carriage theback-and-forth movement of a point on said chain in directions parallelto a line connecting the axes of said wheel members, means to mount saidtrack means to permit the same to be oscillated about a central axis, apair of control members carried by said track means at a point betweenthe pivotal point and one end thereof, a rotating cam member embraced bysaid control members, the periphery of said cam member being so formedthat said control members will remain stationary with respect to theaxis of said cam member at two periods during one rotation of the camand will be moved in one direction at one of the intervening periods andin a reverse direction at the other of the intervening periods, andmeans for driving said chain and said cam member in synchronism.

11. Apparatus for applying materials to surfaces, including sprayingmeans, a track, means to mount said spraying means for reciprocation onsaid track in position for ejecting material in a directionperpendicular to said track, means for reciprocating the spraying means,and means to cause periodic track movements such that at least a portionof the line of movement of the spraying means in each generally forwarddirection will be at an unvarying angle with a similar portion of theline of each return movement of the spraying means.

12. Apparatus for applying materials to surfaces, including sprayingmeans, a track, means to mount said spraying means for reciprocation onsaid track in position for ejecting material 7.

in a direction perpendicular to said track, means for reciprocating thespraying means, and means to cause periodic track movements such thatthe central portion of the line of movement of the spraying means ineach generally forward direction will be at an unvarying angle with thecento mount said spraying means for reciprocation on said track inposition for ejecting material in a direction perpendicular to saidtrack, means for reciprocating the spraying means, and means to move thetrack when the spraying means is at each end thereof in a manner suchthat the spraying means is retracted, so as to permit the same to beadvanced as it moves to the other end of the track.

14. Apparatus for applying materials to surfaces, comprising means tomove a surface along a path, spraying means, a track extending from sideto side of said path, means to mount said spraying means forreciprocation on said track in position to eject spray in a directionperpendicular to said path, means to reciprocate said spraying means,and means to cause track movements such that the spraying means will beadvanced at the same speed as a surface being moved along said pathduring both forward and return movements of the spraying means over saidpath and will be retracted at intermediate periods.

15. Apparatus for applying materials to surfaces, comprising means tomove a surface along a path, spraying means, a track extending from sideto side of said path and beyond the side edges thereof, means to mountsaid spraying means for reciprocation on said track in position to ejectspray in a direction perpendicular to said path, means to reciprocatesaid spraying means from end toend of said track, and means to causetrack movements such that the spraying means will be advanced at thesame speed as a surface being moved along said path during both forwardand return movements of the spraying means over said path and will beretracted at intermediate periods when said spraying means is beyond theside edges of the path.

16. Apparatus for applying materials to surfaces, comprising'a pair ofwheel members, an endless chain member extending over said wheelmembers, a guide element carried on said chain member, areciprocableelement formed with a groove extending perpendicularly to a lineconnecting the axes of said wheel members and embracing said guideelement, a track for said reciprocable member, a spraying member carriedgroove extending perpendicularly to a line connecting the axes of saidwheel members and embracing said guide element, a track for saidreciprocable member, a spraying member carried by said reciprocablemember and arranged to direct spray in a directionperpendicular to saidtrack during the movementof the reciprocable member along the same, andmeans to cause track movements when the spraying memher is adjacent eachwheel member to cause a retraction of the spraying members so that thesame may be advanced during its movement toward the other wheel member.

18. Apparatus for applying materials to sur- 100 faces, comprising apair of wheel members, an endless chain member extending over said wheelmembers, a guide element carried on said chain member, a reciprocableelement formed with a groove extending perpendicularly to a lineconmeeting the axes of said wheel members and embracing said guideelement, a track for said reciprocable member, means for moving asurface along a path traversing a region located centrally with respectto said track, a spraying member carried by said reciprocable member andarranged to eject spray upon said region, means to mount said track foroscillation at an axis intermediate its ends, and means to cause saidtrack to move in one direction about said axis when the spraying meansis adjacent one end of its course, and to move in the other directionabout its axis when the spraying means is adjacent the other end of itscourse and to remain stationary at intermediate periods.

ERICSSON H. MERRII'I. RICHARD W. STANLEY.

